Sting jet signature associated with a high wind event in Scotland (storm Ulli,
3 January 2012)

A rapidly intensifying mid-latitude cyclone was responsible for a high wind
event as it moved over Scotland on 3 January 2012. Meteosat-9 WV7.3 images (below)
revealed two notable signatures: (1) the formation of a pronounced area of warm/dry
water vapor brightness temperatures (bright yellow to orange color enhancement)
over the open water north of Ireland, which indicated a strongly forced region
of rapidly descending middle-tropospheric air, and (2) a classic sting jet**
signature (Monthly
Weather Review | Wikipedia)
which then moved eastward across Scotland. Just to the south of the sting jet
signature, a wind gust of 78 knots was recorded at Glasgow at 08:20 UTC, followed
by a wind gust of 70 knots at Edinburgh at 08:50 UTC. There were additional
reports of wind gusts in excess of 87 knots at non-METAR sites in Scotland.
A comparison of 1-km resolution NOAA-19
VIS0.6 channel and IR11.0 channel (animated GIF, 1057 KB, source: CIMSS)
images at 12:54 UTC showed the structure of the cyclone as it was centered over
the North Sea between the British Isles and Norway.

Amendement (Theo Steenbergen, 16 January 2012)

In the strong westerly flow, a cold front rapidly moved across the North Sea,
passing the Dutch coast in the afternoon of 3 January (see Met-9
HRV Animation, 10:00-14:30 UTC, animated GIF, 5718 KB). The front was accompanied
with a squall line, visible in the radar image as a narrow band of intense rain.
The coastguard ('Rijkswaterstaat') reported a so called meteotsunami at the
coast at Ijmuiden, with a sea level change (rise and fall) of over 1.5 meters
in 30 minutes.

**Definition of a sting jet from Browning (2004): "The
most damaging extratropical cyclones go through an evolution that involves the
formation of a bent-back front and cloud head separated from the main polar
front cloud band by a dry slot. When the cyclone attains its minimum central
pressure, the trailing tip of the cloud head bounding the bent-back front forms
a hook which goes on to encircle a seclusion of warm air. The most damaging
winds occur near the tip of this hook–the sting at the end of the tail."